Inspection Of Resistance

NOTE:

Drain the engine coolant. See COOLING SYSTEM SERVICE WARNINGS and ENGINE COOLANT REPLACEMENT .
Disconnect the ECT sensor connector.
Remove the ECT sensor.

Fig 1: Identifying Engine Coolant Temperature Sensor Connector
Courtesy of MAZDA MOTORS CORP.
Place the sensor in water with a thermometer, and heat the water gradually.

Fig 2: Testing Engine Coolant Temperature Sensor
Courtesy of MAZDA MOTORS CORP.
Measure the resistance between the ECT sensor terminals using an ohmmeter.
- If not as specified, replace the ECT sensor.
- If ECT sensor is okay, but PID value is out of specification, perform the "Circuit Open/Short Inspection". See CIRCUIT OPEN/SHORT INSPECTION .
Specification

Fig 3: Engine Coolant Temperature Sensor Resistance Specifications (1 Of 2)
Courtesy of MAZDA MOTORS CORP.

Fig 4: Engine Coolant Temperature Sensor Resistance Specifications (2 Of 2)
Courtesy of MAZDA MOTORS CORP.
Reconnect the ECT sensor connector.